Germicidal detergent bar



United States Patent 3,240,711 GERMICIDAL DETERGENT BAR George G. Wittwer, deceased, late of Hawthorne, N.Y., by John Wittwer, executor No Drawing. Filed Apr. 9, 1965, Ser. No. 447,106 The portion of the term of the patent subsequent to Sept. 25, 1979, has been disclaimed 12 Claims. (Cl. 252-106) This application is a continuation-in-part of pending application Serial No. 697,807, filed November 21, 1957, which is a continuation-in-part of the following applications, now abandoned, namely, application Serial No. 603,229, filed August 10, 1956, which is a continuationin-part of application Serial No. 369,505, filed July 21, 1953, which, in turn, is a continuation-in-part of application Serial No. 221,746, filed April 18, 1951.

This invention relates to a soap free detergent bar or cake, essentially composed of synthetic detergents and containing a germicidal agent for antiseptic action. The bar of this invention hereinafter particularly described has highly efficient cleansing and germicidal properties.

Elemental iodine is well known to have extremely effective antisetpic properties. However, its use is somewhat limited by its highly corrosive nature and its well known tendency to stain. Certain preparations of iodine do not have these negative properties as, for instance, a saturated solution of iodine in water. Aqueous solutions of iodine, however, are not widely used because the very low solubility of iodine in water (33 mg. in 100 cc. at 25 C.) limits the amount of iodine available for action on bacteria or extraneous protein.

The most widely used preparations of iodine are the well known aqueous alcohol solutions of tinctures. The alcohol used in these preparations has a rapid rate of evaporation which causes irritation and discomfort when the preparation is applied to open wounds, cuts or abrasions. The concentration of alcohol in the solution can be somewhat reduced by taking advantage of the solubilizing action of alkali metal iodides on iodine in aqueous solution. However, this reduces the penetration properties of the tincture and such solutions stain the skin and any cloth with which it is contacted. Also when the solvents evaporate a precipitate is obtained which pro duces the local irritation and corrosion experienced with alcohol tinctures. If too much solution is applied and excessive iodine precipitated, sublimation results on uncovered areas and epidermal blistering where the treated area has been covered.

Surface active agents repeatedly have been shown to increase the solubility of water insoluble compounds by an action which involves incorporating the insoluble compound in molecular aggregates called micelles. These micelles are formed in the bulk of the solution when a definite concentration of the surface active agent has been exceeded. Unlike miscible solvents, such as alcohol, the effect of surface active agents in increasing the solubility of an insoluble compound becomes pronounced in relatively dilute solutions whereas miscible solvents have little effect on the solubility unless high concentra tions of the solute are used. This phenomenon of surface active agents has been utilized in the pharmacy of some drugs. Iodine may be solubilized by anionic, cationic and non-ionic surface active agents.

Applicant has found that the solubilizing effect of surface active agents on iodine can be utilized effectively in combination with certain synthetic detergents and satu- 7 3,240,711 Patented Mar. 15, 1966 rated anionic surface active agents to produce a highly efiicient germicidal detergent in solid cake or bar form. The saturated anionic surface active agent primarily acts as a binder but provides partial solubilizing action on the iodine and some detergent action as hereinafter explained. As primary solubilizers for the iodine applicant uses nonionic water soluble surface active agents. These and all other surface active agents used to form the bar should be saturated compounds since iodine reacts readily with unsaturated aliphatic groups. The surface active agents should have pHs in the range of neutrality (pH 7) and the pH of the mixture should be adjusted to a value in the non-alkaline range as low as is consistent with good cleansing properties for optimum germicidal results. This may be accomplished by adding an acid or a salt such as monopotassium phosphate in amounts such as to product the desired pH preferably in the range of pH 4 to pH 7. In combination with the non-ionic and anionic surface active agents in addition to the solubilizing effect, the following effects are observed: (1) The partial pressure of the iodine is reduced. (2) Its corrosiveness is re duced. (3) Its stability in Water is increased. (4) Its tendency to stain is eliminated. (5) Its toxicity to living tissue is reduced. (6) Its germicidal activity is increased. Thus, the objectionable properties of conventional iodine preparations are eliminated or reduced while the desired anti-septic properties not only are not impaired but actually increased.

DETERGENT BAR COMPOSITION Non-soap, or so-called synthetic detergents, include the alkali metal salts of sulfated aliphatic alcohols, the sulfonated hydrocarbons, the fatty acid esters of hydroxy alkane sulfonic acids, the alkylaryl sulfonic acids, particularly those of the benzene series, the fatty acid amide of methyl amino ethane sulfonic acid, and the alkyl ethers of polyoxyethylene glycols.

It is difiicult to form non-soap synthetic detergents into satisfactory bar shapes without the use of binding agents having undesirable properties such as imparting a gritty feel to the bar and without generally impairing its usefulness as a general purpose detergent. Such solid cakes forms of these synthetic detergents as can be effected with known available binding agents also tend to slough off to a high degree and become softened at a rapid rate upon standing in the presence of moisture. These bars are generally of high solubility and have a higher degree of hydroscopicity than conventional soap, and therefore are subject to these defects to a higher degree than is conventional soap.

A satsfactory all synthetic detergent-iodine bar can be made having excellent lasting properties and a pleasing feel, with no impairments to the inherent detergency, sudsing, lat-hering and germicidal properties by combining an alkyl aryl synthetic detergent with the stearic acid ester of hydroxy ethane sodium sulfonate and/or the lauric acid ester of hydroxy ethane sodium sulfonate as a binder or binders. The germicidal action of this bar is furnished by the elemental iodine non-ionic surface active agent mixture which is incorporated in the bar as the active ingredient.

The binders mentioned in the preceding paragraph are relatively insoluble. The stearic acid ester of hydroxy ethane sodium sulfonate has a solubility in the order of 0.17% or 1.7 parts per thousand in distilled water at sulfonate has a solubility in the order of 0.46% or 4.6

parts per thousand in distilled water at 21 C. The stearic and lauric acid esters of hydroxy ethane sodium sulfonate produce some detergent action and when one or both are combined with the alkyl aryl sodium sulfonate detergent and with the non-ionic surface active agent iodine mixtures in accordance with the process described below, they not only effectively bind the alkyl aryl sulfonate detergent and surfactant-iodine mixtures into a proper acceptable detergent iodine bar, but contribute their detergency to the mixture in a synergistic manner to the end that the total available detergency exceeds the sum of the individual detergencies of alkyl aryl sulfonate detergents and the stearic and/or lauric acid esters of hydroxy ethane sodium sulfonates.

The stearic and lauric acid esters contained no unsaturated hydrocarbon groups, amide linkages or hydroxy radicals common to surface active and sudsing agents of similar chemical structure which do not provide effective binding action for the detergent.

These binders are variously referred to as sodium stearoyl isethionate, or sodium B-stearylethane sulfonate and as sodium lauroyl isethionate, or sodium B-laurylethane sulfonate. (B means beta here and elsewhere hereinafter.) These saturated isethionates can be prepared by the esterification of the respective fatty acid and isethionic acid with subsequent saponification. Examples of these esterifications are described in Reissue Patent No. 28,823.

The alkylaryl sulfonate synthetic detergents used in the preparation of applicants synthetic detergent cakes are classified as anionic synthetic detergents, and chemically can be represented generally by the formula R-R' SO Na where R is an alkyl radical or group of alkyl radicals having an average of at least carbon atoms, and preferably from 12 to 18 carbon atoms, and R is an aryl radical, generally of the benzene series, which may be modified by additional short-chain alkyl radicals. In commercially available alkylaryl sulfonate detergents the alkyl component, R, is generally a straight chain radical having at least 10 carbon atoms, such as decyl and R is phenyl. However, the alkyl component need not be of uniform length for each molecule, but may consist of a mixture of different molecules, the average carbon chain length of the alkyl radical being about 10 carbon atoms. This is particularly true in the case of dodecyl benzene. Some commercially available dodecyl benzene detergents contain uniformly straight chain dodecyl radicals. Others, such as those derived from kerosene fractions and referred to as keryl benzene detergents, contain a mixture of alkyl substituted benzene sulfonates wherein the alkyl radical averages C These are nevertheless referred to as dodecyl benzene compounds. Other compounds of the alkylaryl sulfonate class of detergents include compounds having modifying alkyl groups on the aryl radical.

Suitable commercial decyl and dodecyl benzene synthetic detergents, and other alkylaryl synthetic detergents within this class, are referred to in a publication entitled Snythetic Detergents, compiled by J. S. McCutcheon, New York, 1950, at pages 120 and following.

For good detergent properties the synthetic detergent cake should contain at least 10% of the alkylaryl synthetic detergent. This may be compounded with various percentages of the stearic and/ or lauric acid ester of hydroxy ethane sulfonate sodium salt binders in the range of from 10-90% of the cake, on a dry weight basis. The proportion of the alkylaryl sulfonate detergent accordingly will be in the range of from 90-10% of the cake, also on a dry weight basis. Other suitable binding agents such as waxes may be added. Fillers or diluents, particularly clays, such as china clay and fullers earth or the like, which add bulk Without impairing the detergent properties or cohesiveness of the synthetic cake also may be used. Sodium sulfate, which is often present as a diluent of the commercial alkylaryl sulfonate synthetic detergent, may be present. Sodium chloride and aluminum sulfate may be included to control the foaming characteristics and improve the feel of the cake. Monopotassium phosphate or other acid salts of a similar nature may be included in small amounts for producing a desired pH in the cake. Emollients, such as stearic acid, lanolin, lecithin, glyceryl monostearate, ethylene glycol stearate, propylene glycol monostearate, or the like, may be included and are generally preferred in percentages up to about 4% when making bars for toilet use. Coloring materials and other special purpose ingredients may also be included. The elemental iodine nonionic surfactant combinations, more specifically described below, are included to make the antiseptic detergent-iodine bar. Preferably the nonionic surfactant-elemental iodine mixture should contain from 10% to 20% iodine and should be used in the compounding of the bar in such amounts as to produce an iodine concentration of from 1% to 7.5% of the dry weight of the bar.

Although it is desirable, for economic reasons, to have various amounts of the fillers incorporated into the bar composition, satisfactory bars having excellent detergent properties, good lasting properties and superior germicidal properties, can be made from combinations of the described detergent, binder or binders and iodinesurfactants without fillers or other additives. Where fillers and additives are included, the combined proportions of the detergent and stearic and/ or lauric acid ester binders will, of course, be less than 100%, and may be as little as 20%. Such a cake may include any one or all of the possible additives and fillers named above, or other materials commonly utilized in compounding of detergent cakes and not incompatible with the iodine mixture in whatever proportions are needed to produce the desired effect.

PREPARATION OF IODINE-SURFACTANT MIXTURE In the preparation of elemental iodine for incorporation into the detergent bar, mixtures of elemental iodine are made with water soluble non-ionic surface active agents (surfactants). All of these non-ionic surface active agents are solubilizers for elemental iodine but not all completely release iodine in water. In the following examples of useful combinations of iodine non-ionic surface active agents, applicant uses both liquid and solid non-ionic surface active agents or mixtures of these. The liquid non-ionic surface active agents in combination with elemental iodine make water soluble mixtures. The solid non-ionic surface active agents solubilize elemental iodine but these do not make water soluble mixtures. Table I gives representative examples of both solid and liquid surfactants mixed with from 10 to 20% of iodine.

Table 1 Percent by wt.

Elemental iodine 10 Iso-octyl phenoxy polyoxythylene ethanol, a liquid 90 Elemental iodine 20 Iso-octyl phenoxy polyoxyethylene ethanol, a liquid Elemental iodine 1O Nonyl phenoxy polyoxyethylene ethanol, a liquid Elemental iodine 20 Nonyl phenoxy polyoxyethylene ethanol, a liquid 80 Elemental iodine 10 Polyoxyethylene ester derivative of mixed resin and fatty acids, a liquid 90 Elemental iodine Iso-octyl phenoxy polyoxyethylene ethanol, a liquid 90 Elemental iodine l0 Polyethylene glycol tertiary dodecylthioether, a

liquid 90 Elemental iodine 1O Polyethylene glycol with molecular weight 6000/7500,

a solid 90 Elemental iodine 20 Polyethylene glycol with molecular weight 6000/7500,

a solid 72 Nonyl phenoxy polyoxyethylene ethanol, a liquid 8 Elemental iodine l0 Polyethylene glycol 4000 monostearate, a solid 90 Although the polyethylene glycols and the polyethylene glycol monostearates in combination with iodine are not Water soluble combinations, they are substantially solubilized when incorporated with the saturated anionic binders and detergent in my bar.

Mixtures Nos. 1-7 of Table I were made by adding the elemental iodine to the liquid non-ionic surface active agents and stirring until the iodine was completely dissolved.

Mixtures Nos. 8 and 10 of Table I were made by melting the solids, adding the iodine and stirring. The solids were kept at their melting points until the iodine was completely dissolved in the melts.

Mixture No. 9 was made by mixing the iodine with the liquid surfactant then adding the solid surfactant and melting the mass. The mass was kept in a molten state until the iodine was completely dissolved in the melt.

PREPARATION OF IODINE-DETERGENT BAR In preparing applicants synthetic iodine detergent bars containing the sodium B-stearylethane and/ or the sodium B-laurylethane sulfonate binders, the sodium alkylaryl sulfonate detergent and the iodine non-ionic surface active agents, applicant melts the binders and detergent together in the mixing process at a fairly high temperature in order to insure that a homogeneous mixture of these ingredients in fused combination is obtained. The bars produced from a mixture of the ingredients which have not been properly fused together will be gritty and sandy, and in use, the lastability and uniform dissolution of the binder, germicide and detergent will be affected. In order to effect the necessary homogeneous mixing and fusion of the ingredients, applicant may first prepare a mixture of the sodium alkaryl sulfonate detergent, the sodium B-stearylethane and/or sodium B-laurylethane sulfonate binders in the solid state, and submit this mixture to a roller mixing operation. Additives, such as acid salts, fillers and other desired ingredients, which may be added in the solid state, also can be incorporated into this dry mix. Applicant then places this mixture in a rotary blade mixer equipped with a steam jacket or other suitable means of heating. Water is added to the mixture in the rotary mixer in an amount of from 15-20% by weight, in order to effect blending of the ingredients. The temperature is raised to from 100 C. and maintained at that level during the mixing of the resulting paste. The mixing is continued at the elevated temperatures until a homogeneous mass has been formed. During this mixing procedure the relatively insoluble sodium B-stearylethane and/or sodium B-laurylethane sulfonate binders become fused with the more soluble alkaryl detergent and the additives, and the water which has been added for proper blending is slowly reduced by evaporation. When the mass has been thoroughly mixed and before the water has been evaporated to the desired end level, applicant adds a determined amount of the iodine non-ionic surfactant mixture to the mass and continues the mixing until these ingredients have been thoroughly blended into and incorporated with the other ingredients constituting the bar. The temperature, When the iodine non-ionic surfactant mixture is added to the mass preferably should not exceed F. Vigorous agitation of the rotary blade mixer should be continued during the process, and the water content has been reduced to the desired point.

Coloring materials, perfumes, and other such additives may be incorporated by mixing the coloring agent or such other additives with the water which is added for blending purposes in the mixing operation of the rotary blade mixer.

When the mass has been thoroughly mixed and the water evaporated to the preferred level, the mixture is formed into bars of the desired shape and size by pressure molding.

The following examples will serve to further illustrate representative compositions of applicants new synthetic detergent iodine bar. The process of mixing and fusing the binder, detergent and iodine non-ionic surface active agent mixture, described above, is used in the compounding of each of the compositions set forth in the tables containing the illustrative examples, it being understood that during the compounding, in addition to the parts of the ingredients enumerated in the tables, water in the amount of from 15-20% has been added during the mixing procedure, and has been evaporated down to about 5% While fusion of the components has been effected during the drying stage. Since the parts given in the tables are on a dry weight basis, the amount of water retained in the cake is not included.

Table II COMPONENT, EXAMPLE NO. AND DRY \VEIGHT PARTS Example N o 1 2 3 4 5 6 Na B-stearyl-ethane sulfonate Na B-lauryl-ethane sulfonate Na dodeeylbenzene sulfonate Na decylbenzene sulfonate Kaolin Opal Wax 75% Parafiin wax,

line wax, MP. 178 Mono potassium phosphate Table INo. 1--

Table INo. 4 Table 1No. 7 Table INo. 8 .g

Total Parts Table II-Continued E xarnple No 7 8 9 Na B-stearyl-ethane sulfonate Na B-lauryl-ethane sulionato Na dodecyl benzene sulfonate Opal Wax 75% Paraffin Wax, 25% Mieroerystalline Wax, M.P 118.

Total parts Commercial polyvinyl pyrrolidoneiodine mixture containing approximately 11% available iodine manufactured by General Aniline and Film Corporation.

class consisting of sodium lauroyl isethionate, sodium 25 stearoyl isethionate and mixtures thereof, and an alkylaryl sulfonate having detergent properties, the alkyl radicals of said sulfonate averaging at least 10 carbon atoms, together with an amount of a germicidal composition effective to create a germicidal effect, comprising l20% elemental iodine and 90-80% non-ionic surface active agent, said sulfonate comprising to 90% of said bar on a dry Weight basis, exclusive of said germicidal composition, and said compound comprising 90 to 10% of said bar on a dry weight basis exclusive of said germicidal composition, and a sufficient amount of water distributed therein effective to blend said constituents.

2. A detergent bar according to claim 1 wherein said compound and said sulfonate together constitute at least by weight of said bar.

3. A detergent bar according to claim 1 wherein said germicidal composition is present in such an amount as to provide not over 7.5% of elemental iodine on a dry weight basis of said bar.

4. A detergent bar according to claim 1 wherein said compound is a 50-50 mixture of sodium stearoyl isethiomate and sodium lauroyl isethionate.

5. A detergent bar according to claim 1 wherein said sulfonate is taken from the class consisting of sodium dodecyl benzene sulfonate and sodium keryl benzene sulfonate.

6. A detergent bar according to claim 1 wherein said surface active agent is taken from the class consisting of polyethylene glycols, nonyl phenoxy polyoxyethylene ethane, polyvinyl pyrrolidone, and polyethylene glycol tertiary dodecylthioether.

7. A method of producing a non-soap composition containing iodine in cake form which consists essentially in forming (1) a mixture of from 10 to 90% of alkali metal salt of B-saturated alkyl-ethane sulfonate in which the alkyl radical is selected from the group consisting of the stearyl radical, the lauryl radical and mixtures thereof with to 10% of an alkyl benzene sulfonate in which the alkyl group has 10 to 18 carbon atoms, adding an amount of water sufficient to effect blending of said mixtures at elevated temperature, heating said mixture to a sufficient temperature and agitating said mixture to form a paste, thereby fusing said mixture to form a homogeneous mass; forming (2) a mixture of about 1020% of iodine with a non-ionic surface active agent; blending said mixtures While maintaining said temperature in such proportions that the final product contains about 1 to 7.5% of iodine, evaporating a substantial part of said water, and forming said blend into a cake.

8. A method according to claim 7 characterized in that in forming said first mixture about 1520% of water is added and the constituents are agitated and heated to not over about C.

9. A method according to claim 8 characterized in that said second mixture is incorporated into said first mixture at said elevated temperature with agitation.

10. A method according to claim 9 characterized in that heating is conducted to reduce the water content in the composition to about 5%.

11. A detergent bar according to claim 1 characterized in that the pH of said cake lies between 7 and 4.

12. A detergent bar according to claim 1 wherein the amount of water is about 5%.

References Cited by the Examiner UNITED STATES PATENTS 2,739,922 3/ 1956 Shelanski 252-106 XR 2,746,928 5/1956 Darragh et al. 252-106 2,759,869 8/1956 Sutton et a1 252-107 XR 2,931,777 4/1960 Shelanski 252-106 3,055,837 9/1962 Wittwer 252-161 OTHER REFERENCES Chemical Week, Dec. 22, 1951, vol. 69, No. 25, pages 19-21.

ALBERT T. MEYERS, Primary Examiner.

JULIUS GREENWALD, Examiner. 

1. A SOLID DETERGENT BAR CONSISTING ESSENTIALLY OF A HOMOGENEOUS MIXTURE OF A COMPOUND TAKEN FROM THE CLASS CONSISTING OF SODIUM LAUROYL ISETHIONATE, SODIUM STEAROYL ISETHIONATE AND MIXTURES THEREOF, AND AN ALKYLARYL SULFONATE HAVING DETERGENT PROPERTIES, THE ALKYL RADICALS OF SAID SULFONATE AVERAGING AT LEAST 10 CARBON ATOMS, TOGETHER WITH AN AMOUNT OF A GERMICIDAL COMPOSITION EFFECTIVE TO CREATE A GERMICIDAL EFFECT, COMPRISING 10-20% ELEMENTAL IODINE AND 90-80% NON-IONIC SURFACE ACTIVE AGENT, SAID SULFONATE COMPRISING 10 TO 90% OF SAID BAR ON A DRY WEIGHT BASIS, EXCLUSIVE OF SAID GERMICIDAL COMPOSITION, AND SAID COMPOUND COMPRISING 90 TO 10% OF SAID BAR ON A DRY WEIGHT BASIS EXCLUSIVE OF SAID GERMICIDAL COMPOSITION, AND A SUFFICIENT AMOUNT OF WATER DISTRIBUTED THEREIN EFFECTIVE TO BLEND SAID CONSTITUENTS. 